255/50R18 tire size
A 255/50R18 tire is 28.04 inches (712.2 mm) tall, 10.04 in (255 mm) wide and fits a 18-inch wheel. In inch notation it is roughly a 28.0x10.0R18 — a "28-inch" tire.
| Overall diameter | 28.04 in | 712.2 mm |
|---|---|---|
| Section width | 10.04 in | 255 mm |
| Sidewall height | 5.02 in | 127.5 mm |
| Circumference | 88.09 in | 2,237 mm |
| Revolutions | 719.3 per mile | 446.9 per km |
| Rim diameter | 18 in | 457.2 mm |
Compare 255/50R18 with another size
Alternative sizes on the same 18-inch wheel
Sizes in use within ±3 % of the overall diameter of 255/50R18:
Plus and minus sizes for 255/50R18
| Size | Wheel | Diameter | Difference |
|---|---|---|---|
| 235/65R16 | Minus 2 (16 in) | 28.03 in | −0.04% |
| 225/70R16 | Minus 2 (16 in) | 28.40 in | +1.29% |
| 245/60R16 | Minus 2 (16 in) | 27.57 in | −1.66% |
| 225/65R16 | Minus 2 (16 in) | 27.52 in | −1.87% |
| 255/55R17 | Minus 1 (17 in) | 28.04 in | +0.01% |
| 235/60R17 | Minus 1 (17 in) | 28.10 in | +0.22% |
| 225/60R17 | Minus 1 (17 in) | 27.63 in | −1.46% |
| 245/55R17 | Minus 1 (17 in) | 27.61 in | −1.53% |
| 255/45R19 | Plus 1 (19 in) | 28.04 in | −0.01% |
| 285/40R19 | Plus 1 (19 in) | 27.98 in | −0.22% |
| 225/50R19 | Plus 1 (19 in) | 27.86 in | −0.65% |
| 235/50R19 | Plus 1 (19 in) | 28.25 in | +0.76% |
| 255/40R20 | Plus 2 (20 in) | 28.03 in | −0.03% |
| 295/35R20 | Plus 2 (20 in) | 28.13 in | +0.32% |
| 285/35R20 | Plus 2 (20 in) | 27.85 in | −0.66% |
| 235/45R20 | Plus 2 (20 in) | 28.33 in | +1.02% |
| 255/35R21 | Plus 3 (21 in) | 28.03 in | −0.04% |
| 295/30R21 | Plus 3 (21 in) | 27.97 in | −0.25% |
| 305/30R21 | Plus 3 (21 in) | 28.20 in | +0.59% |
| 265/35R21 | Plus 3 (21 in) | 28.30 in | +0.94% |
Vehicles approved with 255/50R18 tires
Models whose Swiss type approval lists 255/50R18 as a standard or optional size (87 approvals in total). Always check your own vehicle's placard or papers.
Source: Swiss Federal Roads Office (FEDRO/ASTRA), open government data. Original data (downloaded 2026-09-29). Data processed by us; errors in processing are ours, not the publisher's.
Nearby 18-inch sizes
- 235/40R18 (−9.4%)
- 235/45R18 (−6.1%)
- 235/50R18 (−2.8%)
- 235/55R18 (+0.5%)
- 235/60R18 (+3.8%)
- 245/40R18 (−8.3%)
- 245/45R18 (−4.8%)
- 245/50R18 (−1.4%)
- 245/60R18 (+5.5%)
- 255/40R18 (−7.2%)
- 255/45R18 (−3.6%)
- 255/55R18 (+3.6%)
- 255/60R18 (+7.2%)
- 265/40R18 (−6.0%)
- 265/45R18 (−2.3%)
- 265/60R18 (+8.8%)
- 275/40R18 (−4.9%)
- 275/45R18 (−1.1%)
- 275/60R18 (+10.5%)
Reading the 255/50R18 size
- 255 — section width in millimetres (10.04 in).
- 50 — aspect ratio: the sidewall is 50 % of the width, 127.5 mm.
- R — radial construction (ZR on the sidewall means a high-speed rated radial; the dimensions are the same).
- 18 — fits a 18-inch diameter wheel.
The load index and speed rating (for example 91V) follow the size on the sidewall. They must meet at least the values on your vehicle's tire placard.